Dell p2719h not detected by Macbook Pro 2016

You are using a StarTech Dock. The DisplayLink Driver (or StarTech's custom version of that DisplayLink Driver) is what might make the DOCK straighten up and fly right.

Dell Display "Drivers", if available, do not work on a Mac AND they are not Drivers at all -- they are just a collection of settings for resolutions and refresh rates. You are not missing anything when you doing not side-load display "Drivers". The Mac asks the display DIRECTLY.

To support more than ONE display, that dock requires a software Driver based on DisplayLink technology.

It is not al all clear whether they intend to support the first display without the use of DisplayLink Drivers.

The difference between your Macs may be that you do not have that Driver loaded on both Macs.

StarTech does not saw openly whether their Dock supports ANY displays without first installing the DisplayLink driver.

Re: direct connection. There are TWO impediments.

The first is HDMI cables:

HDMI cables you want for HDMI-only Displays (higher resolutions than 720p TV sets) are marked as Certified with an anti-counterfeiting tag and are labeled:

"Premium High Speed HDMI cable" or that + "with Ethernet" --OR--

"Ultra High Speed HDMI cable" or that + "48G"

Cables with No Certification tags are good for your standard 720p TV set, and not much more.

the second is how to get Mac displays recognized:

The Mac uses a system that reminds me of “Plug and play” to determine what display is connected, and what its capabilities are.

To get a Mac display to become active, you need the Mac to query the display, and the display to answer with its name and capabilities. Otherwise, the display will not be shown as present, and no data will be sent to the display. "No signal detected" is generated by the DISPLAY, not by the Mac.

This query is only sent at certain times:

• at startup

• at wake from sleep — so momentarily sleeping and waking your Mac may work

• at insertion of the Mac-end of the display-cable, provided everything on that cable is ready-to-go

• hold the Option key while you click on the (Detect Display) button that will appear in Displays preferences (from another display)

so try doing some of those things and see if the display comes alive.

________

Drivers:

What display-makers refer to as Drives are simply profiles for a particular display. They can be useful for Windows, but MacOS asks the display DIRECTLY, and does not rely on side-loaded profiles (pushed as "Drivers")

That appear to be a 1902 by 1080 display with HDMI, displayPort, and VGA inputs.

Exactly what docking station?

I get good feelings when I can be helpful.

YOU did the "heavy lifting". I just stood around and made some suggestions.